Usually, a wireless communication system includes a receiver and a transmitter. When the wireless communication system works in a Time-Division Duplex (TDD) mode, its receiver and transmitter need to share a common antenna. Therefore, a circumscribed transmitter/receiver switch (T/R switch) is required to switch between receiving mode and transmitting mode. In other words, when the wireless communication system is in use, the T/R switch is configured to selectively connect the antenna to the receiver or the transmitter.
In existing wireless communication systems, the T/R switch is connected with the receiver in series. When the wireless communication system works in receiving mode, the T/R switch will be in short circuit state. When the wireless communication system works in transmitting mode, the T/R switch will be in open circuit state.
Furthermore, both the receiver and the transmitter have a complicated circuit structure, thus when the circumscribed T/R switch is introduced, it is hard to make the wireless communication system having a low insertion loss.